Lisna is a folder tree type music player. It's free.
All basic operations are in single window and there is no screen transition. Lisna provides you a simple and clear operation.

Available Format:
mp3, ogg, mid, wav, 3gp, aac, m4a, flac(*1), wma(*2)
(*1 .flac is Android3.1 and more)
(*2 .wma is available only when your device supports the format)

Main Features:
- Repeat(single track, tracks in a folder, all tracks)
- Shuffle(tracks in a folder, all tracks)
- Play folder including sub-folders (long press and select the folder)
- Remote control by external devices such as headphone or earphone(play, stop, change tracks)
- Available for earphones with single button (press button once to stop, twice to play next track, three times to play previous track)
- Simple rewind and fast-forward
- Folder skip
- Sleep timer(auto stop)
- Change root folder by explorer(keep pressing any folder for few seconds to set it as a root)
- Auto stop when headphone or earphone is unplugged
- Auto stop when you get an incoming call
- Resume track (you can playback where you left)
- Equalizer and extra volume control
- Home screen widget
- Lock screen widget (android4.0 or higher)
- Gapless playback (android4.1 or higher)
- Operation in the notification area (android4.1 or higher)
- Hard Key Operation(Only when the screen is off, you can use the volume control button to skip or reverse tracks. You can also play and stop by pressing the power button twice)

Note:
- Playback may stop due to the power saving function of the terminal. In that case, set Lisna so that it is not subject to power saving.
(For Android 8.0: Open [Settings]-> [Battery]-> [Apps for which power saving function is not applicable] to exclude Lisna.)
- Since it is not a resident service type, music will stop when the application is closed. If you want to play in the background, press the home button.
- If the music stops frequently in the background, try turning off the level meter from "Settings".

Required Authority:
- Access to storage
It is used to play music files on the device.
- Microphone / Recording
Used to display the level meter (scale that moves up and down according to the sound).
I'm only analyzing the sound waves, not recording them.
- Telephone / call status monitoring
Needed to stop the music when the call comes in.
- Bluetooth
Used to open the Bluetooth settings screen.

Languages ​​Supported:
Japanese,English